Clinically vulnerable patients are among Scots waiting longer than 12 weeks for Covid vaccine boosters in some parts of Scotland due to supply issues.

A woman who has a serious heart disorder says she told that there were no appointments for second doses of the AstraZeneca vaccine in the Lothian area for the next four weeks.

She was told it would be June before she receives the booster jag, a gap of 14 weeks and exceeding the recommended 12 week timeframe.

The 58-year-old has hypertrophic cardiomopathy and is in group six, for adults with underlying health conditions, some of whom are clinically vulnerable.

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A spokeswoman for National Services Scotland said there would be rare occasions where individuals would be unable to have booster vaccinations at the sheduled time due to vaccine stocks or clinics being at capacity.

The Scottish Government said the green book of clinical guidance for vaccinations states that if there is a longer than recommended interval between doses, the second dose should still be given, preferably using the same vaccine as was given for the first dose unless they are at "immediate high risk". 

However, patients are advised to contact the helpline if the gap is longer than 11 weeks.

The woman said she was told that only certain sites in Lothian were offering the AstraZeneca vaccine.

She said: "I phoned a week last Friday to find out date of my second vaccination and was told it would be in June which will be 14 weeks (since first vaccination).

"They read out a statement from NHS Scotland saying this delay is okay. I asked to complain and they directed me to NHS Lothian number who were less than pleased as they are not a complaint line but a booking line. 

"They have moved on to the 30/40 age group without completing group 6 clinically at risk."

More than 2.9 million people across Scotland have now had their first doses of Covid vaccines.

A spokesperson for NHS National Services Scotland (NSS) said: "On rare occasions, individuals may currently be unable to have second-dose appointments scheduled.

"This may be due to clinics in their area being full or not having access to stocks of the same type used for the first dose.

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"The availability of appointments changes regularly as vaccine supply becomes available or additional capacity or clinics are set up by local health boards.

"Appointment availability can be checked via the national vaccine helpline on 0800 030 8013, daily from 8am to 8pm and the online portal."

"We understand this can cause frustration but would urge anyone in this situation to continue to check regularly."

People aged 30 to 39 in the UK will be offered an alternative to the AstraZeneca vaccine as a precaution due to a very small risk of rare blood clots. 

The Joint Committee for Vaccination and Immunisation is not banning the use of the vaccine in this age group, but said where the Pfizer or Moderna vaccines were available they should be used preferentially as long as this does not cause any substantial delays to the vaccination programme.

The UK still remains on track to give all adults a first vaccine dose by the end of July, according to England's deputy chief medical officer Professor Jonathan Van Tam.